ENCRYPTION METHOD AND DEVICE

摘要

The invention relates to an economical method and device for implementing even high-performance encryption functions in an encoder consisting of only a PC, software device or similar or any preferred terminal or information system, with an integrated Vernam cipher which does not need to be supported by expensive crypto-hardware for the necessary encryption process. The crypto-hardware consists of either a chip card or a multi-functional PC interface adapter (PCMCIA module) with built-in special crypto-hardware. The encryptor is simply a conventional PC, a software device or another terminal which requires no crypto-technology other than the very simple Vernam cipher (for example, EXOR), even for wideband applications in software. The external crypto-modules all contain complex crypto-functions which produce the Vernam key in reserve. These reserves are temporarily stored in an intermediate memory and then used up progressively by the encryption process through logical operations. Said memory can be installed in either the PC/terminal or in the crypto-module. The encoder always operates with the same Vernam cipher, even if the external crypto- or PCMCIA modules use different symmetrical and asymmetrical ciphers. External crypto-modules in the form of chip cards or PCMCIA modules are economical to produce. All of the complex crypto-functions are outside of the encryptor. They can be interchanged by module and can be performed in the inexpensive and somewhat slower crypto-modules suggested by the invention.